diff options
| author | Eric Dumazet <edumazet@google.com> | 2022-05-12 20:23:09 -0700 |
|---|---|---|
| committer | Andrew Morton <akpm@linux-foundation.org> | 2022-05-13 07:20:19 -0700 |
| commit | cd8c1fd8cdd14158f2d8bea2d1bfe8015dccfa3a (patch) | |
| tree | 01fc533d07cdad9e159c67577b430be341d0bcd1 /mm/page_owner.c | |
| parent | fe30ddca9f18fb56bf1dd161ffd9d8a04bba5713 (diff) | |
mm/page_owner: use strscpy() instead of strlcpy()
current->comm[] is not a string (no guarantee for a zero byte in it).
strlcpy(s1, s2, l) is calling strlen(s2), potentially
causing out-of-bound access, as reported by syzbot:
detected buffer overflow in __fortify_strlen
------------[ cut here ]------------
kernel BUG at lib/string_helpers.c:980!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 4087 Comm: dhcpcd-run-hooks Not tainted 5.18.0-rc3-syzkaller-01537-g20b87e7c29df #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:fortify_panic+0x18/0x1a lib/string_helpers.c:980
Code: 8c e8 c5 ba e1 fa e9 23 0f bf fa e8 0b 5d 8c f8 eb db 55 48 89 fd e8 e0 49 40 f8 48 89 ee 48 c7 c7 80 f5 26 8a e8 99 09 f1 ff <0f> 0b e8 ca 49 40 f8 48 8b 54 24 18 4c 89 f1 48 c7 c7 00 00 27 8a
RSP: 0018:ffffc900000074a8 EFLAGS: 00010286
RAX: 000000000000002c RBX: ffff88801226b728 RCX: 0000000000000000
RDX: ffff8880198e0000 RSI: ffffffff81600458 RDI: fffff52000000e87
RBP: ffffffff89da2aa0 R08: 000000000000002c R09: 0000000000000000
R10: ffffffff815fae2e R11: 0000000000000000 R12: ffff88801226b700
R13: ffff8880198e0830 R14: 0000000000000000 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f5876ad6ff8 CR3: 000000001a48c000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600
Call Trace:
<IRQ>
__fortify_strlen include/linux/fortify-string.h:128 [inline]
strlcpy include/linux/fortify-string.h:143 [inline]
__set_page_owner_handle+0x2b1/0x3e0 mm/page_owner.c:171
__set_page_owner+0x3e/0x50 mm/page_owner.c:190
prep_new_page mm/page_alloc.c:2441 [inline]
get_page_from_freelist+0xba2/0x3e00 mm/page_alloc.c:4182
__alloc_pages+0x1b2/0x500 mm/page_alloc.c:5408
alloc_pages+0x1aa/0x310 mm/mempolicy.c:2272
alloc_slab_page mm/slub.c:1799 [inline]
allocate_slab+0x26c/0x3c0 mm/slub.c:1944
new_slab mm/slub.c:2004 [inline]
___slab_alloc+0x8df/0xf20 mm/slub.c:3005
__slab_alloc.constprop.0+0x4d/0xa0 mm/slub.c:3092
slab_alloc_node mm/slub.c:3183 [inline]
slab_alloc mm/slub.c:3225 [inline]
__kmem_cache_alloc_lru mm/slub.c:3232 [inline]
kmem_cache_alloc+0x360/0x3b0 mm/slub.c:3242
dst_alloc+0x146/0x1f0 net/core/dst.c:92
Link: https://lkml.kernel.org/r/20220509145949.265184-1-eric.dumazet@gmail.com
Fixes: 865ed6a32786 ("mm/page_owner: record task command name")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Acked-by: Waiman Long <longman@redhat.com>
Acked-by: Shakeel Butt <shakeelb@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Diffstat (limited to 'mm/page_owner.c')
| -rw-r--r-- | mm/page_owner.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/mm/page_owner.c b/mm/page_owner.c index fb3a05fdebdb..19bc559e4904 100644 --- a/mm/page_owner.c +++ b/mm/page_owner.c @@ -168,7 +168,7 @@ static inline void __set_page_owner_handle(struct page_ext *page_ext, page_owner->pid = current->pid; page_owner->tgid = current->tgid; page_owner->ts_nsec = local_clock(); - strlcpy(page_owner->comm, current->comm, + strscpy(page_owner->comm, current->comm, sizeof(page_owner->comm)); __set_bit(PAGE_EXT_OWNER, &page_ext->flags); __set_bit(PAGE_EXT_OWNER_ALLOCATED, &page_ext->flags); |